1 files changed, 22 insertions, 0 deletions

diff --git a/src/lisp/std.lisp b/src/lisp/std.lisp
index c723a13..8350482 100644
--- a/src/lisp/std.lisp
+++ b/src/lisp/std.lisp
@@ -22,5 +22,27 @@
           accumulator
           (cdr ls))))
 
+(define (map func ls)
+  (if (null? ls)
+      '()
+      (cons (func (car ls))
+            (map func (cdr ls)))))
+
+(define (filter pred ls)
+  (if (null? ls)
+      '()
+      (if (pred (car ls))
+          (cons (car ls) (filter pred (cdr ls)))
+          (filter pred (cdr ls)))))
+
+(define (member? item ls)
+  (if (null? ls)
+      #f
+      (or (eq? item (car ls))
+          (member? item (cdr ls)))))
+
+(define (assert expr)
+  (assert-eq #t expr))
+
 (define (sum ls) (fold 0 + ls))
 (define (product ls) (fold 1 * ls))